Improved composite gas-retort



diluted gieten @tutti .dtttra Letters Patent No. 94,7 14, dated September 14, i869.

t The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern Beit known that I, JOHN Cocnnnnn, of the city and county of `N ew York, and State of- New York, have invented a new and useful Improvement in the Construction of Retorts for the `Manufacture of Goal- Gas and other purposes; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, making part of this specification.

'.lhe object of my invention is to make a tight and durable retort, using for that purpose iron and fireclay in combination, the iron forming an interior lining(i and the fire-clay the exterior covering thereof; an

My improvement relates to the means by which the tire-clay is secured to the iron.

To enable others skilled in the art to make and use m'y invention, I will proceed to describe the manner of constructing tbe same.

I make the retort 'ol' 'such size and shape as will suit the purpose to which it is'to be applied.

The interior portion A A is a thin cast-iron shell,

and forms a metallic lining for the retort, andthe exterior portion B B is hre-clay, or other suitable maf terial. Upon the outer surface of the iron casting A A, I make numeroussmall protuberances, or hemispherical bosses, D D D, to embrace and hold the feet of the anchors or clamps O 0 C, which are made of small round bar-iron, bent at l'ight angles near Ithe foot, so as to lie parallel with the surface of the casting, and within the thickness of tlie lire-clay covering; or they may be rooted or attached to the casting at both ends, as shown at O C C, Figure 2, or' they may be T-headed, or of any form or construction that will hold or clamp the clay to the casting. These anchors or clamps are secured to the retort in the following manneri The pattern from which the retort is moulded has upon it-s surface the necessary number of hemispherical bosses D DD, each of which has a deep cavity in the centre, to receive the foot of the anchors, and the anchors being` placed Ain these bosses, are rammedup i-n the sand or mould, and are left there on withdrawing the pattern, in the manner well known in the art.'

On pouring the molten metal into the mould all the anchors are .instantly secured in position, and combined with the casting by means of thesebosses.

The interior lining AA being castwith its clamps in position, is covered with fire-clay, ina plastic state, to the proper thickness, during which operation the casting is mounted on bearings at its ends in any con- .venient manner, to permit. of rotation on its axis, so

as to facilitate the covering and moulding-process. The retorts should then be allowedA to dry or harden in the shade, after which theymay be fire-hardened, in the ordinary manner, or they may beplaced in the bench and hardened by the heating-fire before or while 1n use.

The tempering of the clay and the treatment o f the retort, after claying, is substantially the same as in the manufacture of nre-brick retorts.

Formerly retorts for the production' of coalgas were exclusively made of cast-iron, but the continued' action of the great heat to which they were necessarily exposed while in operation, rapidly destroys the integrity of the ironl and causes it to crack into numerous fissures or openings, through which the gas escapes` from the retort into the fire-chamber -and is wasted.

An iron retort seldom continues perfect for more than three months, but they are generally allowed to remain in use for a longer time before removing them from the fire-chamber, on account of vthe trouble and expenseof reconstructing the bench, notwithstanding the great wastage of gas thus incurred.

. In consequenc of the inability of cast-iron to resist the action of heat, hre-clay has been resorted to as a material for..makng retorts, and it has proved much more durable than iron for that purpose; but firebrick being a porous substance, the gas readily passes through it when new, and will continue to do so till the pores are lled up with the g'osser particles that are carrie into them, bythe more subtile elements in their outward passage;` in time, however, the adhesion of the material appears to be so reduced by the action of the percolating gases, that numerous cracks occur, which afford a ready exit to the gas.

The wastag om fire-brick retorts, from these causes, notwithstanding their apparent durability,l is so great, when compared with the wastage and expense of iron retorts,tliat many intelligent and careful gas-engineers consider the iron retorts the more economical of the two.

The retort herein described, combining the impermeable properties of the iron with the refractory properties of the {ire-brick, must necessarily produce the greatest possible economic result, for'it is obvious that there can be no wastage of the gas from such retort, as the iron lining is impervious; andas this iron lining secures the proper form and integrity of the retort, so long as it is protected from the action of the external heat by its ire-brick covering, no cracks or fissures can occur, and consequently no wastage of the gas can take place from the retort while this condition or relation ofthe parts is maintained, for as the two elements of this composite retort mutually sustain each other, such retort must be more durable and more economical than if composed of either element'A separately.

The combination of an iron lining with a fire-clay covering has heretofore been essayed, by means of longitudinal metallic straps or flat bars, secured to the retort upon the outside of the clay covering, to

.hold the clay to the iron,4 and more recently bythe use of numerous small spines castwith-and upon the iron lining, by which to pin the clay to the iron; and

also by means of numerous holes or openings cast in the action of the continued fire-heat to which the retort ifs-necessarily exposed while i-noperation, leaving the clay to yseparate and drop off from the iron lining when these supports are'destroyed, and thus exposing the iron lining to certain and rapid destruction. i

The small spines or thorn-like projections, above re-v ferred to, must be very numerous indeed to answer a useful purpose, and being sharp and brittle, such castings are exceedingly difficult to handle or transport, even from the foundry, Without receiving great darnage from the breaking oii' of these spines; and the plan of holding the clay to the iron lining by means of holes or openings cast in the lining for that purpose, is manifestly but little better' than the common clay retort, as the gases will escape more or less through such holes or openings in the' iron lining.

My mode of construction is not only clear of all these defects, but it possesses,in addition, this important commercial advantage: the iron lining, with its wrought-iron clamps complete, may be transpo'nted from the foundry to any distance with perfect safety and may therefore be transported to a remote' gasworks, without having the clay covering thereon,l at 'a saving of about two-thirds the freight upon a com- 'plete' retort, as it may be clayed-at such gas-works, and be fire-hardened in position in the bench, by the actual operation of making "gas, and thus greatly cheapening the cost of such retorts. y

VHaving thus described the nature and construction of my improvements in ret-Orts, for the production of coal-gas and for other purposes, and shown wherein my mode of construction differs from those plans which have heretofore A been essayed to obtain the the same 1result,

What I claim therein as my own invention, and desire to secure by Letters Patent of the United States,

1. A retort, for the production of coal-gas, or other purpose, having its interior portion of iron, and its exterior portion of fire-clay or fire-brick, or other refractory substance of 'analogous character, in which the iron lining and fire-clay covering are combined with each other, in the manner and by the means substantially as described.

2. The hemispherical bosses, or their equivalents, in combinationrwith the anchors or clamps and the interior casting, constructed in the manner and for the purpose substantial] y as described. I,

' l JOHN OOGHRANE.

Witnesses:

EDWARD LYON, Jr.,

JAMES HUNTER. 

